Characterization of Flow and Hardening Parameters of 1100 Aluminium Alloy by Combining Nanoindentation Test and Crystal Plasticity Finite Element Simulation

The mechanical response of crystalline materials is affected by the flow and hardening of dislocations; that to describe them as a material model in finite element calculations, the flow and hardening parameters are implemented in the crystal plasticity code. In the present study, flow and hardening parameters for 1100 aluminium alloy were characterized by combining the experimental nanoindentation test and 3D crystal plasticity finite element simulations. Extracted parameters were validated by comparing the stress-strain curves of the experimental uniaxial tensile test and simulation of 3D crystal plasticity finite element on single crystal and polycrystal models. Also, the effect of the friction coefficient in determining the flow and hardening parameters was discussed. The results of this study showed that (i) parameters of initial yield stress, reference shear strain rate, and saturation stress, respectively had the highest positive correlation with the maximum load; (ii) the load-displacement curve obtained from the simulation of the nanoindentation test using the characterized parameters has a relative error of 0.50% compared to the experimental nanoindentation test at the maximum indentation depth; (iii) The characterized parameters significantly can estimate the yield stress and ultimate tensile strength with a relative error of 2.60% and 0.20% for the single crystal model and 10.18% and 12.44% for the polycrystal model, respectively. However, while accurately modeling the yield zone in the polycrystalline model, the accuracy of the characterized parameters is affected by the grain boundary orientation.